Currently, in order to suppress the influence of the threshold voltage of the driving transistor in the pixel circuit of the organic light emitting diode display apparatus on the luminance of the organic light emitting diode, a threshold voltage compensation function has been realized in the pixel circuit, thereby compensating for the influence of the threshold voltage of the driving transistor on the luminance of the organic light emitting diode. For the whole organic light emitting diode display apparatus, the phenomenon of nonuniform luminance or flicking of the whole organic light emitting diode display apparatus, due to the nonuniformity and drifts of the threshold voltages of the driving transistors of respective pixels, may be reduced.
However, in the display process of the organic light emitting diode display apparatus, the gate-source voltage is continuously applied between the gate and the source of the driving transistor of each pixel, and thus the threshold voltage drift of the driving transistor of each pixel will increase continually. When this threshold voltage drift is in a certain extent, the threshold voltage drift may be compensated by the above mentioned threshold voltage compensation function. However, the above mentioned threshold voltage compensation function becomes inactive when this threshold voltage drift exceeds the certain extent, and accordingly, the display effect of the organic light emitting diode display apparatus is getting worse, thereby reducing the lifespan of the organic light emitting diode display apparatus.
Therefore, there is a need for a pixel circuit and a display panel capable of reducing the threshold voltage drift of the driving transistor of each driving circuit and prolonging the lifespan of the organic light emitting diode display apparatus.